Tractor for agricultural or road work



Dec. 4, 1951 DUFOUR TRACTOR FOR AGRICULTURAL OR ROAD WORK 5 Sheets-Sheet 1 Filed Sept. 5, 1945 Ivvzwrae Lsogv DuFo we,

ATmRA/EY Dec. 4, 1951 1.. DUFOUR 2,577,237

TRACTOR FOR AGRICULTURAL OR ROAD WORK Filed Sept. 5, 1945 v r 3 Sheets-Sheet 2 .l'uvsm'roz LEO/v DuFoue,

Dec. 4, 1951 DUFOUR TRACTOR FOR AGRICULTURAL OR ROAD WORK 3 Sheets-Sheet 3 Filed Sept. 5, 1945 Fig.5

ATTORNEY Patented Dec. 4, 1951 T OFFICE TRAo'rOR FoR AGRICULTURAL OR ROAD WORK Leon Dufour, Geneva, Switzerland Application September 5, 1945, Serial No. 614,507 In Switzerland November 21, 1944 Claims.

Designs have been proposed in the past fora tractor for agricultural or for road Work comprising two main parts, one of which being tiltable in a vertical plane with respect to the other around the axis of the driving wheels or around an axis parallel and close to the axis of the driving wheels. The stationary part, stationary during this relative motion, comprises a frame or chassis carrying on its rear the driving wheels of the tractor and on its front end the guiding wheel or wheels. It is equipped also with the usual drivers seat. The tiltable or pivoted part constitutes a two arm rocking beam. The front arm carries the motor together with all its accessory parts such as fuel tank, radiator, air cooling fan, etc., and the housings containing the complete mechanisms for gear shifting, backward drive and differential gear usual in tractors, that is the whole mechanism serving for the transmission of the power from the engine to the driving wheels. The agricultural machines or the devices used for the coupling of loads to be towed by the tractor are fastened to the rear arm of the rocking beam.

In such a tractor the tilting of the pivoted part is obtained, without any additional mechanism, through the mere rearing reaction due to the ad-- hesion of the driving wheels to the ground. But,

, in such cases it is frequently wished to momenthe soil is inclined backward, the tractor being then pulled backward by its own weight.

It has already been suggested to make use of the application of the'rear wheel brakes in order to increase the rearing reaction and impart an increase of energy for tilting the pivoted part of the tractor (Swiss Patent 191,773, French Patent 798,961, English Patent 464,900, 13.. S. Patent 2,058,964, etc.) but in the just mentioned patents, erroneous means only have been indicated to obtain this result. As a matter of fact, in these patents, only one form of design of the tractor has been described in which the pivoted part is rotatable around an axis parallel and close to that of the driving wheels. In the Swiss Patent 191,773 referring only to that particular form of design of the tractor, it has been precisely stated that the brake shoes were mounted on the chassis. Now, in such a case, the desired effect is unattainable because the whole brake moves with respect to the chassis when the pivoted part rotates around its axle, which is not coaxial with the rear wheels. If then the brake shoes were mounted on the chassis, they would prevent all tilting motion of the pivoted part. The brake shoes and their support, called the brake support, must be mounted therefore on the pivoted part of the tractor described in these patents; this means that they move bodily with the rear axle housing of the tractor and applying the brakes does not cause the desired tilting motion. Indeed, if the brakes mounted in such a manner are app1ied, the pivoted part shall be imparted by the friction of the brake drums in a rotation in the same direction as the driving of the rearing reaction. Thus, the stronger the wheels this direction being just opposite to that brakes are being applied, the more the tilting effect coming from the rearing reaction is being counteracted, which is just the opposite of the desired result. At the limit, when the brakes are jammed on the Wheels, the engine shall be completely stopped, but the desired tilting shall not have taken place.

The present invention has for its object to provide tilting energy to the pivoted part when the brakes are applied to the driving wheels, thus avoiding the errors mentioned above. The invention. consists in combining in such a tractor having a pivoted part two characteristics already known separately, but of which it was not ascertained as yet that the simultaneous action was necessary to cause the desired efiect.

The invention consists in the designing of the pivoted part of the tractor in such a manner that it. can rotate only around the axis of the rear driving wheels and in designing the brake shoe carriers, or brake supports in such a manner as to .be embodied in the stationary part of the tractor and not to the pivoted part. Under these conditions, the pivoted part shall be able to be tilted .freely When the brakes are set. Applying the brakes on the stationary chassis shall increase the effect of the rearing reaction instead of counteracting it. The invention consists further in providing the central portion of the brake supports with journal bearings embracing the ends of the rear axle housing which is a component of the pivoted part of the tractor, and to fasten the chassis against these brake supports. Said ends of the rear axle housing must be on their outside concentric with the axis of the driving wheels. The pivoted part, in its tilted motion shall rotate at the same time around the axle of the driving wheels and around the internal face of the stationary journal bearings provided in the central portion of the brake supports. A slightly different design consists in arranging the journal bearing surfaces provided inside the .brake supports such manner that they embrace .directly both Lhalf axles of the driving wheels, outside and externally to the outer bearings of said half axles provided in the ends of the rear axle casing of the..tractor. The pivoted part of the tractor would 'thenxotate around the axle of the driving wheels alone. Another design would consist in locatingitheabearings inside the brake supports in .theiorm of separate elements, and in clampingzsamezaga'inst said supports taking proper care for their careful centering with respect to the bore. Lastly; the chassis may be fastened either directly against -.the brake supports or their bearings, :or .indirectly Thy means of intermediate shelvescast in one -piece with the brake supports or :their hearings, or still by means =of intermediate separate :shelves applied to the .brake supports .or -to their bearings.

Figs. 1 .to'6- of thaannexed-drawing, given-here as examples, represent a tractor embodying the present invention as well .as 'various details of its design;

Fig. :1 is aside wiew in elevation .of a .tractor aatrestequippedwith a-carriedploughthe, pivoted rpartaof .the tractor :resting on the chassis;

:Fig. .2 is aiside view of .thezsame tractor .in operation, the-pivoted part'beingstilted,qthe plough sbeingrset in :the:soi1;;

Fig. .3 is-a.t-1a;larger scale "a partial cross .sec- ;tionin a'vertical planeof the rear axle assembly =01 the :tractor with its .left driving .wheel, the whole being viewed from the back;

:Fig. 4 is across section in a horizontal-plane :of the-same rear axle assembly;

5 is acrosssection in a vertical iplaneof =a portion of the rearaxlezassembly in which :a slightly difierent form .of design vof the bearing iior =the;pivoted;par.t .is'shown;

Figure 6 is a cross sectional .viewin a vertical .plane -of another .form of .the .present invention.

.-In -the Figures .1 :and 2 theleft front guiding wheel as well as ;the left rear dri ving wheel .of the :tractor are supposed to be :removed .for .the saketoficlarity. In the Figures 4, .5 .and .6,.thc zdriving wheel has not been represented, .but its hub .is :shown. 'In Figures 1 :and .2, .l .is the LChaSSiS-DI' stationary part of the-tractor, having at the front, the guiding wheels .2 and .at the *rear the driving-wheels .3. Numeral 4 represents the-engine with its :radiator :5 and its.,gaso1ine .oroil tank 6. Numeral .1 is thesteering wheel, :located above the gear lbox .8 fcontaining the .clutch and the whole mechanism :for .speed changing and .for .the transmission of power from the engine .to the rear wheels, differential sgear included. PartsA, 5,-6, 1, .8 .make up .the ,pivoted .part .of the .tractor which is rotatable arouncltheaxle ;9 of the-driving wheels, being guided ina journal bearing .(the details vvo'f which maybe .seen in .thejigures 3 .to .6) located inside the vbrake support .I'fl. .Thus .the pivoted ,part may be. termed .a..ro.cking"beam;having .two arms, A.and.B,lone..on each side of the axle '9 around which .it.ro.cks, so.as-.to tiltarm A with respect .to the plane'of the chassis l and arm .B .with respect .to the ground surface at the rear of the tractor. The brake support is gfastened to the .40 :c'oncentr'i'c with the .axle .9.

I 4 chassis at l3. A pedal ll allows the driver to actuate the brake acting directly on the driving wheels of the tractor. A pull on a lever l6 actuates a latch mounted on the chassis thus liberating a notched keeper I! on the pivoted part of the tractor. The plough carried at the rear being somewhat heavier than the engine With itS accessory partsfithegpivoted part shall ..tilt backwards and the tractorshall take'the posi- 10 tion shown in Fig. 2, in which like numerals rep- ..resent like parts. If the tractor is in a forward drivi g .position, the rearing reaction developed hyLth'e rearwheels in contact with the ground, will increase the tilting force of the pivoted part 35 randcwill apply the plough strongly against the soil. In order .to increase the force applying thejploughjagains'tthe soil, it is only necessary to press on the pedal II of the brake IQ of the zrearfdriving wheels. Indeed, the rearing reaction increases with the action of the brakes on the :driving wheels. Inversely, when .the tractor is -in reverse :gear, the 'opposite rearing reaction will tend to bring the pivoted;part-back to its :positionishownin Fig. 1. But, ifthe groundslants slightly in the back, the tangential :force exerted .by the driving wheels :on the .soil will be small .if :not nil, and the rearing reaction will "be :too small to vcause the lifting of the plough. It .Wlll xbe sufilcient then to act .on thepedal ll "of :the brake of :the driving wheels to create a strongreversed rearing reaction. Theplough will 'belifted immediately and the notched keeper on ithe'hinged part .williengage the latch was shown in "the Figure .1. v

.In Fig.3; the brakersuppoitt is has :in' its central iportiona journal hearing 1'9 embracing the end 21B :of theatubulariendtll vof the :rear axle hous- .ing;22 :of :the tractor. Said :end 28 :is machined :ex'teriorlyrm order -"to rpresenta surface precisely As the "rear axle thousing belongs :to the :zpivoted part :or rocking beamtof ?thetrac'tor,:it'wil1 .turns'imultaneously with the tbeam :around'ithe :axle'9 hi :the driving wheels and inside the bearing 19 provided .inrthe :centr-al Iportion lOf the brake :support 18. .The chassis l, shown 'Jhere .in the :shapenf-a "U is fastened directly against :the brake support 18. The shoes zfl of the brake H] are shownlin .cross section. "The brake-drumifi and thexhub .25lof the rear drivingiwheel 'aare one singlevpiece. A key locksthe'axle li in thehub 25.

-Fig. 4 represents the same details, but viewed as a horizontal .cross section. The chassis l is shown from :above. 'In thisfiguraone sees the pivoting axle 24 of the brake shoes, carried by 'the brake support I8 and also the spreading cam "25 -for said shoes together with its :control lever 2l. "The cam shaft rotates-in a bearingfzt provided inthe brake support 1'8.

Fig. 5 shows a'slightly different arrangement in which the bearing '29 provided in 'thecentral'portion of the brakesupport l8 embraces "directly the extension of the axle 9, between the hearing-23 provided in the end of the horn 2! :of 'the rear axle "housing and the hub "25 'of thereardriving wheel. With this arrangement, when the hinged part shall be "tipped, it will rotate solely around the shaft "9 which rotates itself in the bearing 29 locatedcentrally in'the .70 brake support [8.

Fi'g.'6;represents another arrangement in which the axle '9 rotates in .a ball bearing (a roller bearing could naturally be used also) located .in the end 253 of the horn .2! o'f'the'rear :axle

.75 housing. .The journal bearing 19 in which the up of two halves, for mounting purposes, as the bearing [9 has a bore smaller than the outer housing of ball bearing 30. The bolt 3| indicates symbolically that the brake support ismade up of two halves bolted together. The chassis l is fastened to' the brake support l8 by means of an intermediate shelf 32 cast in one piece with the support 18.

'While I have illustrated and described only three embodiments of my invention, it is to be expressly understood that the present invention is not to be strictly construed as being limited to the embodiments herein'illustrated. For example, the scope of the appended claims in additionto covering these embodiments specifically are also of a scope adapted to cover a tractor having a tilting body, brake supports for brakes acting on the rear drive wheels, which are made as a part of the non-tilting chassis of the tractor and not as a part of the tilting part of the tractor like the prior art arrangements.

I claim: a

1. In a tractor of the type consisting of a wheeled non-tilting chassis including rear drive wheels, a rigid elongated body mounted to rock on an axis coinciding with the axis of the rear drive wheels so as to tilt with respect to said non-tilting chassis, a power plant for said tractor mounted on the said body to one side of the said axis, a driving connection between said rear drive wheels and said power plant, aground engaging implement carried by the body on the other side of said axis and trailing the said rear drive wheels, brake means for said drive wheels mounted on said non-tilting chassis, whereby tilting forces are imparted to said elongated rockably mounted body by the reaction from the force applied to the rear drive wheels by said power plant and the tilting torque around the rear wheel axle is increased when the brakes to the rear drive wheels are applied.

2. In a tractor of the type consisting of a wheeled chassis including rear drive wheels, a rigid elongated body mounted to rock on an axis coinciding with the axis of the rear drive wheels, a power plant for said tractor mounted on the said body to one side of the said axis, a driving connection between said rear drive wheels and said power plant, a ground engaging implement carried by the body on the other side of said axis and trailing the said rear drive wheels, means for retaining the power plant end of said body connected to the chassis in nonrocking position, to thereby hold said implement raised above the surface of the ground, brake means for said drive wheels mounted on said non-tilting chassis, whereby tilting forces are imparted to said elongated rockably mounted body by the reaction from the force applied to the rear drive wheels by said power plant and the tilting torque around the rear wheel axle is increased when the brakes to the rear drive wheels are applied.

3. A tractor for non-wheeled ground engaging implements comprising two main parts, one of said parts being a wheel supported chassis having a rear drive axle, and the other part comprising a beam medially pivoted on said axle and tiltable with respect to the plane of said chassis, said beam supporting the tractor power plant in front of the axle and the said ground engaging implements to the rear of the axle, a

driving connection between said power plant-and said rear drive axle, brake means for said drive wheels mounted on said non-tilting chassis, whereby tilting forces are imparted to said elongated rockably mounted body by the reaction from the force applied to the rear drive wheels by said power plant and the tilting torque around therear wheel axle is increased when the brakes to the rear drive wheels are applied.

4. A tractor for non-wheeled ground engaging implements comprising two main parts, one of said parts being a wheel supported chassi having a rear drive axle, and the other part comprising a beam medially pivoted on said axle and tiltable with respect to the plane of said chassis, said beam supporting the tractor power plant in front of the axle'and the said ground engaging implements to the rear of the axle, a driving connection between said power plant and said rear drive axle, means for tilting the beam on said axle teeter-fashion to engage said implements with the ground, latch means for retaining said beam non-tilted in the same plane with the chassis, brake means for said drive wheels mounted on said non-tilting chassis, whereby tilting forces are imparted to said elongated rockably mounted body by the reaction from the force applied to the rear drive wheels by said power plant and the tilting torque around the rear wheel axle is increased when the brakes to the rear drive wheels are applied.

5. A tractor comprising a .chassis, ground engaging wheels mounted at the front and rear ends of said chassis, a rear axle mounted transversethe chassis and having a driving wheel journalled on each end thereof, a brake drum on each of said rear wheels, brake shoes supported'on said chassis, means for engaging said brakeshoes with their respective brake drums, a body part tiltable with respect to the said chassis pivoted on said rear axle so that the front part thereof swings vertically above the chassis and the rear part thereof swings vertically above the ground back of the rear wheels of the tractor, said front part supporting the power plant of the tractor and said rear part supporting ground tilling means, a driving connection between said power plant and the said rear axle, latch means mounted on said chassis and said front part of the tiltable body, means adapted to release said latch means to thereby permit said body to tilt and engage the said tilling means with the ground at the rear of the tractor, and brake supports on the chassis for supporting the brakes acting on the rear wheels, whereby, the force of said tilting action of the tiltable body part is increased by the engagement of said brake shoes with the drums mounted on the drive wheels when forward tractive power is transmitted to the drive wheels to increase the normal tilting force applying the tilling means into the ground.

6. In a tractor of the type consisting of a wheeled chassis including rear drive wheels, a rigid elongated body mounted to rock on an axis coinciding with the axis of the rear drive wheels, a power plant for said tractor mounted on the said body to one side of the said axis, a driving connection from the power plant to the said drive wheels, a ground tilling implement relatively heavier than said power plant carried by the said body on the other side of said axis, whereby the weight of said implement tends to rock said body angularly with respect to the non-rockable wheeled chassis, and friction sam gaar rneans having; cooperating parts mounted for engagement with each-other on said-chassis and said. drive-wheels to produce a brake torcnieto allow a tilting torque produced by the drive wheels-- to be transmittedv by the driving connection to a housing of the tiltable" parti jour nailed on the driving wheel. axle;

'7. In. a' tractor of the: type having? a wheeled chassis including rear drive wheels-mounted: on an 'axle, a housing journal-led on' said axle havingtubular ends; a body constituting atiltable rigid two. arm' rocking beam medially secured to said housing, the front arm of saidbeam having mounted thereon a pWerplant assembly for transmitting power to said rear drive wheels, therear arm of said beam supporting ground tilling meansadapted to engage with the'ground whensaid beam rocks around the axis of said axle with said housing journalled thereon, brake supportsmounted on said chassis, frictional brake shoes carried thereby, and brake drums on said rear wheels adapted tUbeT engaged by said brake shoes, whereby transmission of'power to said drive wheels from said plant and engagement 'or" said brake shoes is effective to apply a force to tilt said beam with respect to: the plane of the said chassis for lowering or raising said tilling means according to the direction: of said power transmission to saidwheels.

8-. In a tractor of the type having awheeled chassis including rear drive wheels mounted on half axle; members, a housing journalled on said axle members having: tubular: ends, aab'ody 'constitutingia tiltablez rigid two, arm. rocking beam medially" secured to said housing; the frontiarm of said beamrhaving mounted thereon: a power plant assembly'for' transmitting power to said rear drive wheels, the rear arm of said beam supporting ground tilling means adapted to enage with the ground when said beam rocks around the aXis ofsaid axle members with said housing journalledi thereon, brake supports s mounted on sai'dichassishaving? journal bearings in their central portions: frictional brake shoes carried thereby andbrake drums on said rear wheels adapted tobeengaged by said" brake shoes, whereby transmission of power to said drive wheels from said plant and. engagement of said. brake shoes is efiective to apply a force totilt said beam with respect to the plane of the. saidv chassis for lowering" or raising said tillingmeans according, to'the direction of said power transmission to said wheels.

9; A tractor according tc'claim 8, in which the said brake supports of said rear Wheel brakes are providedin theircentral'portion with journal bearings, said journal bearings embracing directly' said axle members of said'driving wheels, outside of the outer'b'earings' of said axlemembers' borne by said tubular ends of said rear axle housing which belong bodily to said tiltable part of said'tractor, in Orderthat; duringtilting motions,.sa'id tiltable part rotates solely around said axle members of: said drivingwheels.

10. A tractor according to claim 8, in which the brake supports of said. rear wheel brakes are provided in their central portion with journal bearings, the unity" of action of' the chassis of said tractorwitn said brake" supports including shelves to which said chassis is fastened, said shelves being. formed in one piece with the brake supports.

LEON DUFOUR.

REFERENCES, crrEn The-gfollowing referencesarei-of' record in the file: of. this? patent:

UNITED STATES PATENTS 7 

